Screw-cutting die



(No Model.)

B. L. HARTMANN.

$UREW UUTTING DIE.

Patented Dec. 27,1881.

fn pen Jar:

I I I rib-l f 1 v fiber e UNITED STATES PATENT OFFICE.

ERNEST L. HARTMANN, OF TOUGHKENAMON, PENNSYLVANIA.

SCREW-CUTTING DIE.

SPECIFICATION forming part of Letters Patent No. 251,435, dated December2'7, 1881, Application filed May 16, 1881. (No model.)

To all whom it may concern: 7

Be it known that I, ERNEST L. HARTMANN, a citizen of the United States,residing at Toughkenamon,in the county of Chester, State ofPennsylvania, haveinvented a new and useful Improvement inScrew-Outting-Dies, which improvementis fully set forth in the followingspecification and accompanying drawings, in Which- Figure 1 is a sideelevation of the die-holder embodying my invention. Fig. 2 is a sect-ionthereof in line as 00, Fig. 1. Fig. 3 is a section thereot'in line y y,Fig. 1. Fig.4. is a side view of the dies removed, and Fig. 5 is aperspective view of the disk detached.

Similar letters of reference indicate corresponding parts in the severalfigures.

My invention consists of means for retaining and guiding thread-cuttingdies in the head or holder, as will be hereinafter fully set forth.

Referring to the drawings, A represents the head or holder, and B thedies fitted thereinto and held adjustable relatively to each other bymeans of screws 0 passed through opposite places of the head and bearingagainst the dies. In the widened portion of the wall of the holder, at aright angle to the screws 0 (J, is an opening, A, in which is fitted adisk, D, the inner face of which is pointed or ribbed, as at a, andadapted to freely enter the groove I), formed on the side of each die B,the two grooves being continuous. Bearing against the back of said diskD is a screw, E, which is fitted to the wall of the holder and appearson the outer side thereof for purposes of operation. The opening A forthe disk D is preferably larger than that for the screw E, or it may besaid to be a'countersink on the inner face of the widened portion of theholder, so that the disk requires to be inserted from within the spaceor way designed for the dies. The disk D is placed in the opening A tofull extent, and the dies B are properly located. The screw E is thenrotated, so that the rib a enters the grooves b of the two dies, auditwill be seen that while said rib acts as a guide on which the diesuniformly slide when moved to and from each other for purposes ofadjustment, the displacement of the dies from the holder is prevented,since the rib projects beyond the inner face of the portion of theholder containing the disk D and enters the grooves b, and so serves toretain the dies in the holder.

I am aware that it is not new to employ a screw-pressed-piece of metalfor retaining the .dies, said piece being countersunk in the head andengaging with grooves in the sides of the dies. This, therefore, I donot broadly claim; but.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

Adie-holder provided with a disk, D, formed with a retaining and guidingface or rib, a, screw E,which holds the disk in position, and theadjusting-screws O O for the dies, said screws being at a right angle tothe screw E, substantially as and for the purpose set forth.

ERNEST L. HARTMANN.

Witnesses:

JOHN A. WIEDERSHEIM, A. P. GRANT.

